In general, chocolate has such a problem that it causes blooming phenomenon during storage to deteriorate its commercial value. This blooming phenomenon is divided into "fat blooming" due to unstable crystals of fats and oils and "sugar blooming" due to recrystallization of sugar. In particular, fat blooming is dominant.
In order to prevent fat blooming, a tempering process is employed from the viewpoint that a fat-and-oil ingredient of chocolate is transferred to a stable crystal form as much as possible and this is considered to be an important step in chocolate production. However, fat blooming is still caused because of, for example, insufficient tempering, temperature changes during marketing and storage stages of chocolate products. In particular, when chocolate products are exposed to a high temperature such as about the body heat for a certain period of time, it is very difficult to prevent fat blooming, even if the products are subjected to an excellent tempering process.
As a method for preventing fat blooming in a case that chocolate products are exposed to a high temperature such as about the body heat, JP-A 63-240745 has proposed a method using a chocolate additive in the form of powdery particles. However, there is a problem that a relatively time-consuming treatment is required to obtain a stable crystal form. In addition, since the apparent specific gravity of the particles is light, certain improvement of their dispersion in a mixture of chocolate ingredients is required.
Further, although, as described above, a tempering process is an important step in chocolate production, normally, such process includes cooling and re-warming (re-heating) steps, respectively, at least once Seika-Jiten (Confectionery Dictionary), page 459, October, 1981, published by Asakura Shoten!. Then, since cooling and heating are involved, great energy loss is caused. In view of this, there is a tendency to omit a tempering process, if possible.
For solving this problem, JP-A 2-406 has proposed a method using shortening for chocolate. This shortening is easily handled and is utilized as useful shortening for omitting or simplifying a tempering operation.
However, in a case of shortening for chocolate comprising as a main ingredient triglycerides whose total carbon atoms are 50 or more, in particular, up to 56, their crystallographic behavior is similar to cacao butter which is one of chocolate ingredients and therefore, when chocolate is exposed to a high temperature at which almost all chocolate products are melted, its function as a material for preventing fat blooming is scarcely expected.
Furthermore, since this shortening contains a considerable amount of fats and oils which are rich in low melting point components, it greatly influences on properties of chocolate. In particular, when a liquid fat is used as a low melting point component, such problem as lowering of heat resistance of chocolate is also caused. Moreover, when such chocolate is coated on a snack such as baked confectionery, the liquid fat migrates to the baked confectionery portion. This migration causes a problem of blooming of complex confectionery such as snack coated with chocolate.